Humidity controller



s. s. GREEN 2,73 ,853

HUMIDITY CONTROLLER March 20, 1956 2 Shee'cs-Sheei 1 Filed May '13, 1955 17c 22b 17b JINvENToR STANLEY SCREEN IIBYMQELZL mm March 20, 1956 s s. GREEN 2,738,853

HUMIDITY CONTROLLER Filed May 13, 1953 2 Sheets-Sheet 2 H N VENTOR,

STANLEY SGREEN :[5 YWQIQL-ZTWI iiETTORNEY United States Patent CONTROLLER Stanley S. Green, Indianapolis, Ind.

Application May 13, 1953, Serial No. 354,670

1 Claim. (Cl. 183--4.3)

This invention relates to a device for controlling the humidity of a room and consists essentially of a receptacle through which air of the room may be carried, such as by an electric fan or blower, across a relatively shallow pan of a desiccating chemical solution and across either a solid, granular or flake form of the chemical itself to discharge the air finally back into the room. A primary purpose of the invention is to provide a relatively cheap structure which may be highly efiiectivem the absence of having to employ any refrigerating units, and which may be operated at a relatively low cost.

A further primary object of the invention is to provide a structure which may be used interchangeably for removing water from air when such an operation is desired, and also for humidifying the air when that condition is desired. The only movable element in the structure consists of a motor and a motor driven fan for circulating the air through the structure.

These andmany other objects and advantages of the invention will become apparent to those versed in the art in the following description of one particular form of the invention as illustrated in the accompanying drawings, in which? Fig. 1 is a view in side elevation and partial section of a structure embodying the invention;

Fig. 2 is a top plan view of an annular tray employed in the structure;

Fig. 3 is a top plan view of a second type of tray employed in the structure; and

Fig. 4 is a view in detail and in elevation and partial section of a unit modified for humidifying air.

A cylindrical shell has a lower end or head 11 fitted thereto, this head 11 having a floor 12 sloping toward the center, and having a central opening through the lowest portion of the floor, this opening being designated by the numeral 13, and from which opening there extends upwardly within the head 12 a cylindrical shell 14. There is also provided a drain pipe 15 extending from the floor 12 at the lowermost part thereof immediately adjacent the juncture of the shell 14 with the floor 12. I

A plurality of abutments such as short posts 16 are mounted in a common plane around the lower end portion of the member 10 to extend inwardly thereof sufficiently to receive a pan 17 thereon. This pan 17, Fig. 3, is shaped to have a marginal upturned Wall 18 of relatively short height such as around about to inch, and the floor 19 is substantially planar. The overall diameter of the pan 17 is less than the internal diameter of the member or housing 10, and a plurality of spacer fingers 20, herein shown as four in number, extend outwardly from the periphery of the pan 17 to serve as spacing members to position the pan 17 substantially centrally of the housing 10 to leave an annular opening between the margin of the tray 17 and the inside face of the housing 10. The pan 17 is provided with a plurality of upwardly extending posts 21, herein shown as 2,738,853 7 Patented Mar. 20, 1956 2 three in number, each of these posts being fixed to the floor 19 of the pan 17 in any suitable manner. The top ends of these posts 21 terminate in a common plane parallel to the plane of the floor 19.

Resting .on these posts 21 is a second type of pan designated by the numeral 22, and illustrated in Fig. 2. This pan 22 has an external diameter approximately equal to the internal diameter of the housing 10, but suflicient- 1y less to permit the pan 22 to be entered freely therein to rest on these posts 21, and have the outer peripheral margin of the pan 22 in close proximity to the wall of the housing 10.

This housing 22 has a depth substantially equal to that of the pan 17, and by being annular in nature, there is the opening 23 left centrally through the pan. The opening 23 has a diameter substantially equal to that of the internal diameter of the shell 14, the shell diameter being such that air may be moved therethrough at a relatively low velocity so that in the movement of air, there is no particular noise noticeable. In the one particular form of the invention as illustrated herein, the diameter of the shell 14 and the diameter of the opening 23 is approximately /3 of the diameter of the housing 10, although this proportion is not indicated as being a limitation of the invention. The pan 22 has the floor 24 substantially planar, and the side bounding walls 25 and 26 are ,sufiicient to retain a depth of water over the floor 24 equal to approximately that held in the pan 17. This pan 24 carries a plurality of posts 27 fixed thereto, herein shown as three in number, spaced around the pan to provide a three point bearing for the next above pan which is identical to the pan 17 and is indicated by the numeral 17a. The pan has its peripheral margin spaced inwardly from the wall 10 in exactly the same manner as is the peripheral margin of the pan 17. In fact, the pan 17a is an exact duplicate of the pan 17, including the spacing fingers 20.

In like manner, trays 17 and 22 are placed within the housing 10 in alternate relation as indicated in Fig. l where the pan 22a rests on the posts 21 of the pan 17a; the pan 17b rests on the posts 27 of the pan 22a; the pan 22b rests on the posts of the pan 1712; the pan 17c rests on the posts of the pan 22b; and the pan 22c rests on the posts of the pan 170. That is, there are a plurality of the pans 17 and the pans 22 arranged in alternating manner one above the other within the housing 10. The number of these pans and the height of the housing 10 will depend upon the capacity of the structure as may be desired.

On the posts 27 of the pan 220, Fig. 1, there is supported a pan 28 which is substantially a duplicate of the pan 17. However, this pan 28 carries thereon a wire or fabric wall 29 cylindrical in shape and terminating by an upper marginal boundary edge 30, somewhat below the upper edge 31 of the housing 10. This wall 29 has its lower edge fixed to the marginal portion of the pan 28 and is so designed that it will retain the chemical desiccant therein as it rests on the floor 28. The openings through the wall 29 are such that the chemical desiccant, such as calcium chloride, may be retained even though it be in granular or flake form.

A cover generally designated by the numeral 32 rests over the top end of the housing 19 to have a gasket 33 fitted over the end 31 of the housing 10, so that there will not be air leakage therethrough or noise due to vibration of the cover 10 against the drum when the fan motor is running.

The cover 32 has an upwardly extending housing 43 herein shown as having a diameter less than that of the overall diameter of the cover 32. The housing 43 is substantially cylindrical in shape, and has its side wall perforated for exit of air. In the present showing of the invention, Fig. 1, the openings through the housing 43 are covered by louvers 34.

Within the housing 43 there is mounted a motor 35 driving a fan 36 suspended thereunder. While the fan 36 is herein shown as being of the blade type, it may be of any of the desired forms, and the invention is not to be limited to that blade type.

The cover rests on top of the housing and is held in place by its own weight. Further fastening is unnecessary. In filling the device with desiccant, the cover is merely lifted off, placed somewhere else, and then lifted on again.

In the drawing, the cover 32 is shown as having a down turned lip telescoping over the upper end of the housing, and there is a gasket 33 carried around the inside of that lip, this gasket 33 being directly over the end of the wall of the housing 10. This is clear in Fig. 1.

The structure so far described is supported in any suitable manner, herein shown as by three legs 37, 38 and 39, attached to the head 11. The outlet 15 where a hose connection is not employed is necessarily supported sufficiently high from the floor to permit a container such as a bucket 40 to be inserted freely under the drain pipe 15 to catch the liquid discharging from the pipe 15.

Operation in operating the structure above described, the chemical used, such as calcium chloride, is poured into the container formed by the wall 29 and the pan 28 by first removing the cover 32, which is frictionally retained in position on the housing 19. After the desired amount of chemical has been added the fan 36 is set into operation. The fan 36 is so designed that it will discharge air through the louvers 34, which means that the interior of the housing 1t tends to be evacuated, and consequently air will flow upwardly through the shell 14, around the outer peripheral margin of the first pan 1'7, then across the top side of that pan 17 to flow upwardly through the opening 23 in the pan 22; thence outwardly toward the wall of the housing 10, around the marginal portion of the pan 17a; thence back toward the center and upwardly through the opening in the pan 22a; thence outwardly and around the marginal edge of the pan 17b; back through the opening through the pan 22b; thence outwardly and around the marginal edge of the pan 17c; back through the opening through the pan 22c; and thence upwardly between the housing 16 and the outside of the wall 19; and finally across and up past the fan 36 and out the louvers 34.

In this travel of the air through the device, the pans 17 and 22 will, of course, be initially dry in case the structure has not theretofore been used or has been cleaned out and then restored for usage. As the air passes across the wall 29, the desiccating action of the calcium chloride is such that globules of water will tend to be formed, and as these globules accumulate, dissolving the calcium chloride, the water will trickle downwardly and be caught in the pan 22c spaced below the calcium chloride carrying pan 23. When this pan 22c has sufficient calcium chloride solution received therein to cause it to overflow, the overflow will tend to trickle downwardly primariiy through the central opening of that pan 22c into the next below pan 17c, and so forth on down until the overllow of the solution has been such that it will drop into the head 11 and tend to accumulate on the floor 12, which accumulation is drained by the pipe 15. The accumulation thus is caught in the receptacle 4!). By reason of the presence of the shell 14 extending well upwardly within the head 11, a tendency for any of that liquid to flow outwardly through that opening is avoided, and any splashing will of course be within the head 11 outside and around the shell 14.

When the solution is caught particularly in the upper pans 22c and 17c, it is normally a saturated solution, and

as the air is drawn over the great area of the surface of the liquid in these pans, the solution itself will take up moisture or water from the air to reduce the percentage of chemical in that solution so that the solution thereby tends to become weaker. In other words, the solution in the lowermost pan 17 is not nearly as concentrated as is the solution in the upper pan 22c, and therefore the use of the chemical calcium chloride, if that be the chemical employed, is reduced to an economical consumption by reason of this arrangement to have moisture taken from the air through the contact of the air over the various degrees of concentrations of the liquid in the various pans.

Further it is to be noted that the farther the air travels from the opening 13 to the discharge openings 34, the more concentrated becomes the chemical with which the air comes into contact, so that there is no opportunity for the air to become more humid after it leaves an initial dehydrating zone. To the contrary, the dehydrating etfect increases as the air flows through the device.

Therefore, it is to be seen that an exceedingly simple and relatively low cost of production structure is presented in this invention, and that the only cost of operation is that of the cost of the calcium chloride or chemical which may be employed plus the cost of the small amount of electrical current which may be employed to operate the motor 35.

The same structure without any mechanical changes therein may be employed to humidify the air such as may be desirable during winter months and particularly where a hot air furnace is employed. To change the structure to a humidifying device from the dehumidifying operation, all that is required is to place within the wall 29, Fig. 4, a vessel or pail containing water, and this vessel, designated by the numeral 41, is provided with at least one small opening 42 at its base from which the water may gradually leak or trickle outwardly to flow down over the pans 17 and 22 as above indicated in the case of the calcium chloride solution. Thus as the air travels through this structure, and discharges through the openings 34, it comes into contact with large surfaces of water, and thereby takes up moisture from those surfaces so that the air discharging through the openings 34 carries a greater percentage of moisture than it did upon entering the opening 13. In this case of humidifying, the rate of flow of the water from the receptacle 41 may be such that there is a slight drip or trickle from the discharge pipe 15, or the discharge may be so regulated that by the time the water flows down over a sufiicient number of the trays to set up the desired degree of humidifying, there will be no discharge at the lower end.

On the bottom tray 17 there is an annular depending lip 44 which need not be on the other trays. It is made by forming an annular groove in the bottom of the tray. It has a diameter somewhat greater than diameter of intake opening 14. The function of this lip 44 is to prevent liquid from travelling laterally beyond it and adhering to the under side of the tray and in some instances dripping through the air intake opening 14 rather than being collected within the head 11. This insures that drainage will always reach the pail 40 by way of the drain pipe 15 which is importanct and especially so if a hose is attached to the drain pipe and depended upon to conduct liquid away to a basement drain instead of collecting it in the pail.

It is desirable that the device be operated in an approximately level position so that the shallow trays will have the full area of their upper surfaces covered with liquid. With good leveling, a considerable portion of the under surfaces of the trays will become wet, too, which increases the effectiveness.

When the device has been operating for some time and all the trays are substantially filled with liquid, the storage capacity in these trays may be considerable. If, under these conditions, the device is tipped, due to 5 moving it, a large part of this stored liquid will spill over suddenly into the collecting head 11. For this reason, although the collecting head 11 normally operates empty, it is essential that it have a volumetric capacity of at least approximately the volumetric capacity of all of the liquid-holding trays.

In use as a room water-adder or humidifier, if desired, the perforated or mesh basket 29 may be entirely removed and a tank substituted. 1 This tank should have the leakage orifice 42 as previously described.

An important advantage of the tray construction here described is that impurities and sludge from commercially impure (and cheap) desiccants (as for instance calcium chloride) are collected and accumulate in the top two or three trays where, they can do no harm in clogging up the device or the drain pipe 15. At conveniently long intervals the trays can be removed and cleaned of these insoluble impurities.

To an important extent the amount of desiccant in the container 29 determines the speed with which the device is able to extract water from the air for a given fan capacity.

To increase the capacity of the device, the container 29 should be kept nearly full of chemical at all times. To lower its capacity, a smaller amount of chemical would be used.

Certain quantitive relations of one particular form of the device which has been satisfactory in operation are of interest although not to be deemed as limitations. These are: maximum solid desiccant capacity, ten to fifteen quarts. Capacity of all trays, seven quarts. Capacity of collecting head 11, seven quarts. Capacity of bucket 40, ten quarts.

If it is desired to speed greatly the action of the device as a humidifier, heat can be addedto the device, preferably in the bottom in the collecting head 11.

In particularly dry climates a modified use of the device is as a room cooler. Warm dry air is taken in through the opening 13 at the bottom and after passing over the trays of water emerges from the louvers 34 at a lower temperature but with a higher water content.

Therefore, it is to be seen that while the invention has herein been described in reference to the particular structure in minute detail, it is obvious that structural changes may be employed without departing from the spirit of the invention, and I therefore do not desireto be limited to that precise form beyond the limitations which may be imposed by the following claim.

I claim:

A portable humidity controller comprising a housing; a plurality of pans inside the housing in a vertically spaced apart relation wherein there is a lower pan receiving liquid overflow from an upper pan, said pans being held in approximately horizontal position and being capable of holding suflicient liquid to cover substantially all the upper surface area of the pans to an appreciable depth when filled to overflowing; the horizontal surface area of each pan being less than suflicient to block the horizontal interior cross-section of the housing, and said pans being spaced to provide a tortuous path for air passing through the housing from bottom to top; humidity control support means carrying humidity control. means positioned over the uppermost of said pans; means for passing air upwardly through said housing; an overflow space for liquid from the pans having a capacity at least approximately the sum of the capacities of all of the pans; said space being located in the lower part of the housing and providing a liquid overflow receptacle below the bottom pan, and a principal airintake conduit entering the bottom of the housing through said overflow receptacle and defining the inner dimensions of said receptacle and discharging into the housing above the maximum liquid overflow level and close to the bottom of the lower pan.

References Cited in the file of this patent UNITED STATES PATENTS 591,058 Rogers Oct. 5, 1897 591,138 Mixer Oct. 5, 1897 894,897 Osborne Aug. 4, 1908 1,850,930 Heid Mar. 22, 1932 1,886,957 Huff Nov. 8, 1932 2,026,935 Downs Jan. 7, 1936 2,091,353 Downs Aug. 31, 1937 2,279,326 Kaufman Apr. 14, 1942 2,390,104 Kaufman Dec. 4, 1945 FOREIGN PATENTS 486,974 France May 21, 1918 681,271 France May 13, 1930 

